A State Rarity Rank of S1 means: Typically 5 or fewer occurrences, very few remaining individuals, acres, or miles of stream, or some factor of its biology makes it especially vulnerable in New York State.

Global Rarity Rank:G1

A Global Rarity Rank of G1 means: Critically imperiled globally because of extreme rarity (5 or fewer occurrences), or very few remaining acres (or miles of stream), or especially vulnerable to extinction because of some factor of its biology.

Did you know?
Marl fens occur where carbonates such as calcite and calcium or magnesium carbonate (marl), precipitate at the surface and plant root zone of a wetland. As ground water rich in these compounds flows upward to the wetland surface at high rates, decreases in the partial pressure of CO2 cause marl to precipate (Bedford and Godwin 2003)

There are probably less than 10 occurrences statewide, and the total acreage is very small. A couple documented occurrences have good viability and are protected on public land or private conservation land. This community is limited to the calcareous areas of the state where marl deposits form on the surface. The current trend of this community is probably stable for occurrences on protected land, or declining slightly elsewhere due to moderate threats related to development pressure, invasive plants, and alteration to the natural hydrology.

The number and acreage of rich graminoid fens in New York have probably declined moderately to substantially from historical numbers, likely correlated with the onset of agricultural and residential development.